Ronnie O’Sullivan remained on course for a record-breaking seventh UK Championship title with a devastating 6-1 win over Jack Lisowski.

In-form world number 17 Lisowski led 1-0 after an encouraging start.

But he missed a number of regulation pots and the five-time world champion capitalised in clinical fashion.

O’Sullivan led 3-1 at the interval and breaks of 118 and 112 helped secure a 17th UK last-eight appearance, against either Ding Junhui or Martin O’Donnell.

In the afternoon’s other fourth-round tie, Scotland’s Stephen Maguire completed an astonishing comeback, scoring three tons as he overturned a 4-0 deficit for a 6-5 victory over world champion Mark Williams.

But the Rocket endured no such drama as became the first man through to the last eight at the York Barbican.

“I was not on my best, best game but I dug in,” said O’Sullivan, on his 43rd birthday.

“It can be difficult to assess a match when you are playing. You need to watch it.

“I haven’t been great in the tournament so far. I have played better, but my consistency is better.

“I still get super, super nervous but you have to find a way to manage that. If you have any aspirations to win, you have to perform under pressure.

“He is great player with great talent and all the shots, but he misses a few easy ones. You can’t afford to do that and win consistently. It can be a tough game.”

Defending champion O’Sullivan was steady before the break but majestic afterwards, with his back-to back tons taking him to a remarkable 982 career centuries.

If he goes all the way at the York Barbican, O’Sullivan would move past six-time UK champion Steve Davis and also surpass Stephen Hendry’s total of 18 Triple Crown event wins.

‘I got my butt kicked’

Bristolian Lisowski has had his best season to date, reaching three ranking quarter-finals, a semi-final and making the final of the Riga Masters,

But he was blown away by O’Sullivan.

“I lost my way after I lost the third frame,” said Lisowski. “He put me under a lot of pressure and I lost my concentration. He’s in good nick and I got my butt kicked.

“John Higgins beat me badly at the World Championship and I came back, so hopefully I can come back stronger again.

“I made it quite easy for him and I missed a lot of balls. I don’t know why I played so badly.”

Seven-time world champion Stephen Hendry said: “He has just been too strong for Jack Lisowski.

“Jack missed too many balls, which is unforgivable against a player as good as Ronnie. It was a pretty emphatic afternoon.”

Majestic Maguire

Maguire makes thrilling comeback to beat Williams

Meanwhile, 2004 UK champion Maguire was in scintillating form to dump out world number two Williams.

Maguire, who faces either Mark Allen or Neil Robertson in the quarter-finals, wasted decent chances in every frame before the interval and was made to pay as he trailed 4-0.

But the turnaround was remarkable – the world number 15 barely missing a ball as he rattled off successive centuries with scores of 122, 120 and 109 to get back to 4-3.

Having levelled at 4-4, the pair exchanged frames before Maguire got over the line by clinching the deciding frame with a brilliant doubled red.

“I have never made a comeback like that so that is up there with my best-ever performances,” he said. “At 4-0 down, I told my dad to get the car ready to go home.

“I started to pull the cue right back and hope for the best. As long as the other guy isn’t on five then you have a chance. And at 4-0 down it couldn’t have gone any worse, but after that it couldn’t have gone any better.

“I should be going home now. I will be free-rolling from now on.”

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